A particularly close relationship between state and effect spaces
exists in GPTs that satisfy the no-restriction hypothesis [1]},
i.e. GPTs with effect spaces consisting of all linear maps
\(e:\mathbb {R}^{d+1}\rightarrow \mathbb {R}\)  such that \(0\le e\left(\omega \right)\le 1\) 
for all \(\omega \in \mathcal {S}\) . In such an unrestricted
theory the state space defines a unique effect space, and vice
versa. The effect space of an unrestricted GPT with state space \({\cal S}\) 
is given by
\(E\left(\mathcal {S}\right) & =\left\lbrace  e\in \mathbb {R}^{d+1}|0\le e\cdot \omega \le 1,\text{ for all }\omega \in \mathcal {S}\right\rbrace  \nonumber \\& =\mathcal {S}^{*}\cap \left(u-\mathcal {S}^{*}\right)\,,\) 
